Tank weigh modules are generally known in the art for weighing material storage tanks, bins, hoppers and process vessels, so that the amount of material in the vessel can be determined. Typically, the entire weight of a tank or other vessel will be supported on three or four weigh modules respectively arranged between the three or four supporting legs of the vessel and the shop floor or other supporting platform. A typical tank weigh module is, in effect, a housing and interface adapted to receive a load cell and transmit the weight load of the vessel onto the load cell, which then carries out the weighing function. A conventional tank weigh module includes a base that can be bolted to the supporting floor, and a top plate that can be bolted to the supporting leg of a tank. The load cell is arranged between the base and the top plate to receive and measure the weight load. A rocker pin may be used for load introduction into the load cell while rejecting side or lateral loading.
It is also known to provide various restraining structures and arrangements to check or prevent an excessive motion between the base and the top plate of the weigh module. Such checking or excess motion restraint is necessary for maintaining the structural integrity of the weigh module in the event that an excessive travel or other unusual motion is applied to the top plate of the weigh module by the tank or other vessel. For example, if the vessel is subjected to wind loading, seismic tremors, or other forces that would cause a swaying or tilting of the tank, then the weigh modules arranged on one side of the tank are subjected to an excessive downward travel while the weigh modules arranged on the other side of the tank are subjected to an excessive uplift travel. Under such circumstances, the weigh modules may also be subjected to tilting or twisting motions. If such unusual and excessive motion is not checked or restrained, then the tank or other vessel could tip over. For this reason, conventional tank weigh modules typically include various complicated configurations of overlift restraint bolts, check rods, stay rods, restraining dogs or protrusions, and the like.
The conventional provision of the above mentioned check rods, stays, overlift protection bolts, and the like has caused several disadvantages in the known tank weigh modules. Most importantly, the overall construction of the conventional tank weigh modules has become rather complicated and costly due to the various restraining measures. Furthermore, the installation and servicing of the conventional tank weigh modules has also become complicated for the following reasons. First, the various restraining measures often need to be adjusted or installed after installation of the tank weigh module in its final intended application. Secondly, the restraining measures hinder or prevent access to the load cell, so that replacement of the load cell in the event of a failure requires a complete removal and disassembly of the tank weigh module. Finally, at least some conventional tank weigh modules are regarded as providing inadequate restraint or protection against overlift, tilting, and side loading conditions.